The downfall of Easter Island may have had more to do with preexisting environmental conditions than degradation by humans, according to a new study of the remote speck of land made famous by its enormous stone-head statues.

Easter Island, also known as Rapa Nui, was first settled around A.D. 1200, and Europeans landed on its shores in 1722. The circumstances surrounding the collapse of the indigenous population of Rapa Nui are hotly debated both in academia and popular culture. Scientist and author Jared Diamond argued in his 2005 book “Collapse: How Societies Choose to Fail or Succeed” (Viking Press) that prior to European contact, the indigenous people of the island degraded the environment to the extent that they could no longer thrive.

The new study suggests that Easter Island’s people were, indeed, suffering before Europeans came along. The story of their downfall, however, may be less about environmental degradation than the pre-existing environmental constraints of the 63-square-mile (163 square kilometers) isle. [Image Gallery: The Walking Statues of Easter Island]

“The results of our research were really quite surprising to me,” said study co-author Thegn Ladefoged, an anthropologist at the University of Auckland in New Zealand. “Indeed, in the past, we’ve published articles about how there was little evidence for pre-European-contact societal collapse.”

Collapse of civilization?

The new study challenged Ladefoged and his colleagues’ view. Changes on Easter Island have been well documented, archaeologically. Over time, elite dwellings were destroyed, inland agricultural fields were abandoned, and people took refuge in caves and began manufacturing more and more spear points made out of volcanic glass called obsidian, perhaps suggesting a period of war and upheaval.

The problem with pinning down the island’s history, according to the researchers, is that the dates of all these events and abandonments remain murky. Going into the study, the researchers expected to find that most of the disaster occurred after Europeans arrived, Ladefoged told Live Science.

To clarify the timeline, the researchers analyzed more than 400 obsidian tools and chipped-off obsidian flakes from six sites scattered around the island, focusing in particular on three with good information on climate and soil chemistry.

Obsidian absorbs water when exposed to air. By measuring the amount of water absorption in the surfaces of the obsidian tools and flakes, the research team was able to gauge how long those surfaces have been exposed, thus revealing when the tools were made. A greater number of tools from a certain time period indicates heavier human use of that area during that time. [History’s 10 Most Overlooked Mysteries]

Natural challenges

The obsidian dates varied widely across the sites. Site 1, on the northwestern coast of the island, saw a steady increase in use between about 1220 and 1650, with a fast decline starting after 1650 — long before Europeans arrived on the island.

Site 2, an interior mountainside site, saw a rapid increase in land use between about 1200 and 1300, a slower increase until about 1480, and then constant use until a decline that started between 1705 and 1710, also before European contact. By the time Europeans came along, coastal Site 1 was at about 54 percent of its peak land use, and mountainous Site 2 was at only about 60 percent.

Site 3 told a different story. This near-coastal area saw a slow increase in human activity between 1250 and 1500, and then a faster increase until about 1690, after which settlement remained fairly constant until after European contact. In fact, the decline in use of this site didn’t begin until 1850 or later, the researchers found.

The differing climates of the sites may explain the uneven decline, the researchers said. Site 1 is in the rain shadow of the volcano Ma’unga Terevaka, making it prone to droughts. Site 2 is wetter, but its soil fertility is low. Site 3, the longest-lasting spot, is both rainy and fertile.

What this means is that the people of Easter Island may have been struggling against natural environmental barriers to success, rather than degrading the environment themselves, the researchers reported Monday (Jan. 5) in the journal Proceedings of the National Academy of Sciences.

“It is clear that people were reacting to regional environmental variation on the island before they were devastated by the introduction of European diseases and other historic processes,” Ladefoged said. The next step, he said, would be to take a detailed look at the archaeological remnants of dwellings on the island over time to better understand how humans and the environment interacted.

FRESNO, Calif. (AP) — Loggers cutting down forests burned in wildfires could bring about the extinction of California spotted owls, wildlife advocates said Tuesday as they sought protection for the birds under the federal Endangered Species Act.

The petition says emerging science has shown that the owls thrive in old growth forests that are still living as well as those that have been burned and turned black by high-intensity forest fires.

That finding contradicts current common practice of the U.S. Forest Service, which opens up some burned forests to loggers, the petition states.

U.S. Forest Service spokesman John Heil said officials don’t believe the California spotted owl is in danger of extinction. The agency maintains that massive wildfires are the greatest threat to the owls and works to ensure the owl’s habitat is maintained or improved, he said.

Spotted owls have declined throughout California by about 40 percent in the past three decades, said Chad Hanson, a forest ecologist at the John Muir Project of Earth Island Institute and one of the petitioners.

There are an estimated 1,200 pairs nesting in the state stretching from Lassen National Forest in the north to San Bernardino National Forest in the south, he said.

Without federal protection, Hanson said the owls could be gone after another three decades of logging.

“You don’t call that a decline,” he said. “Science is telling us loudly that this species is at serious risk of extinction.”

The U.S. Fish and Wildlife Service, which denied protection to the spotted owl in 2006 under a similar request, has three months to decide if there is evidence to support the request and open a deeper discussion. Officials at the U.S. Department of the Interior and U.S. Fish and Wildlife Service declined to comment, saying they had not yet seen the 130-page petition.

Rangers monitor California spotted owls and are currently updating a 1992 study to determine what help is needed. That study should be ready early next year with a conservation strategy complete by 2016, Heil said.

Mike Albrecht, a logger and owner of Sierra Resources Management, said removing burned trees creates healthier forests, which benefits spotted owls and people. Loggers have left large swaths of forests in California untouched, which are open to wildlife, he said.

“It’s a little misleading to blame logging or massive fires or any one thing on the demise of the spotted owl,” he said. “We’re all working hard to preserve it.”

Monica Bond, a biologist with the Wild Nature Institute and one of the petitioners, said a 400-square-mile area burned in the 2013 Rim Fire is a prime example of the logic in the petition.

Spotted owls have flourished a year after the Sierra Nevada’s largest fire in recorded history raced through Stanislaus National Forest and Yosemite National Park, she said. Hanson and Bond have taken part in a lawsuit attempting to stop logging in the Rim Fire area.

“The fact is that logging is going to hurt owls,” she said. “It’s time to give this owl some help.”

One of the reactors in Europe’s largest nuclear power plant in southern Ukraine suffered an accident that triggered an automatic shutdown this week. Reports suggest that damage occurred to a transformer in one of the 1000-megawatt reactors at the Zaporizhye plant, which provides over one-fifth of the country’s electricity.

Ukraine’s energy minister said that it was a “technical fault” and assured the public that there was “no threat” to the reactor’s safety, according to BBC News.

With the country already suffering fuel shortage, Ukraine this winter will probably be forced to import electricity from Russia.

Accidents at nuclear rectors makes folks understandably nervous, and is also a reminder that despite all the climate change benefits we get from nuclear energy – like cutting greenhouse gas emissions – there are a lot of risks associated with it, too.

Three Mile Island, Chernobyl and Fukushima all grabbed the world’s attention over the past 30 years when the crises unfolded at those plants. But what happened after they left the headlines?

The facility was only 3 months old when a cooling problem caused one of the reactors to overheat and release radioactive gases and iodine into the environment, but it wasn’t enough to cause any confirmed health effects to local residents.

The reactor was shut down permanently, was decontaminated and put into what is known as “post-defueled monitored storage,” with plans for dismantling only after its neighbouring reactor on site is shut down sometime in 2034.

In April 1986, the world’s worst nuclear disaster occurred at Ukraine’s Chernobyl power plant. technicians lost control of nuclear fission reactions in the reactor core and heat rose quickly until pressure built up and explored the core, releasing radioactive steam into the atmosphere. After the initial explosion occurred, fire broke out that sent large clouds of radioactive particles high into the air, which was then swept over a large part of Western Europe.

Thirty-one people – technicians and firefighters mostly – died from the accident itself, and untold thousands may have contracted cancer. Exact numbers are still being debated.

If you want to see the devastation that this nuclear accident wrought in its immediate surroundings check out newly-released video footage obtained via a remote-controlled drone. This is the first time that the nearby ghost town Pripyat has been filmed from the air.

The power plant itself is entombed within an aging concrete structure that was hastily built back during the old Soviet era.

Currently, an internationally-funded project is underway to build a massive 32,000 ton metal arch that will contain the entire building. Hopes are that it will be ready by 2017, before the existing shelter collapses and releases more radioactive-laden dust into the atmosphere like a dirt bomb. It is expected that the arch should last anywhere from 100 to 300 years.

Finally, the March 2011 Japanese earthquake and tsunami showed us that there can be natural forces that have to be considered with nuclear power. The Fukushima Daiichi power plant, located 220 km northeast of Tokyo on Japan’s east coast, had three of its six reactors melt down when it got hit by tsunami waves triggered by a 9.0 earthquake. This knocked out its generators which caused its reactors to overheat, explode and release radioactivity into the environment – contaminating food, water and air.

Over 300,000 people were evacuated from the surrounding villages. Nearly 16,000 residents are still unable to return to their homes because clean up efforts are being hindered by unsafe levels of radiation in the soil and water.

All this radiation from the disaster has definitely not been isolated to just Japan. Researchers monitoring the Pacific Ocean, in which much of the radiation spilled into, have detected radioactive isotopes this past November just 160 km off the coast of California.

OKUMA, Japan (AP) — More than three years into the massive cleanup of Japan’s tsunami-damaged nuclear power plant, only a tiny fraction of the workers are focused on key tasks such as preparing for the dismantling of the broken reactors and removing radioactive fuel rods.

Instead, nearly all the workers at the Fukushima Dai-ichi plant are devoted to an enormously distracting problem: a still-growing amount of contaminated water used to keep the damaged reactors from overheating. The amount has been swelled further by groundwater entering the reactor buildings.

Hundreds of huge blue and gray tanks to store the radioactive water, and buildings holding water treatment equipment are rapidly taking over the plant, where the cores of three reactors melted following a 2011 earthquake and tsunami. Workers were building more tanks during a visit to the complex Wednesday by foreign media, including The Associated Press.

“The contaminated water is a most pressing issue that we must tackle. There is no doubt about that,” said Akira Ono, head of the plant. “Our effort to mitigate the problem is at its peak now. Though I cannot say exactly when, I hope things start getting better when the measures start taking effect.”

Workers wearing protective gears stand on the water tank that stores contaminated water at the Fukus …

6,000 WORKERS

Every day, about 6,000 workers pass through the guarded gate of the Fukushima Dai-ichi plant on the Pacific coast — two to three times more than when it was actually producing electricity.

On a recent work day, about 100 workers were dismantling a makeshift roof over one of the reactor buildings, and about a dozen others were removing fuel rods from a cooling pool. Most of the rest were dealing with the contaminated water, said Tatsuhiro Yamagishi, a spokesman for Tokyo Electric Power Co., or TEPCO, the utility that owns the plant.

The work threatens to exhaust the supply of workers for other tasks, since employees must stop working when they reach annual radiation exposure limits. Experts say it is crucial to reduce the amount and radioactivity of the contaminated water to decrease the risk of exposure to workers and the environmental impact before the decommissioning work gets closer to the highly contaminated core areas.

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40 YEARS

The plant has six reactors, three of which were offline when disaster struck on March 11, 2011. A magnitude-9.0 earthquake triggered a huge tsunami which swept into the plant and knocked out its backup power and cooling systems, leading to meltdowns at the three active reactors.

Decommissioning and dismantling all six reactors is a delicate, time-consuming process that includes removing the melted fuel from a highly radioactive environment, as well as all the extra fuel rods, which sit in cooling pools at the top of the reactor buildings. Workers must determine the exact condition of the melted fuel debris and develop remote-controlled and radiation-resistant robotics to deal with it.

Troubles and delays in preparatory stages, including the water problem and additional measures needed to address environmental and health concerns in removing highly radioactive debris from atop reactor buildings that exploded during meltdowns, have pushed back schedules on the decommissioning roadmap. Recently, officials said the government and TEPCO plan to delay the planned start of fuel removal from Units 1 and 2 by about 5 years.

The process of decommissioning the four reactors is expected to take at least 40 years.

A Tokyo Electric Power Co. (TEPCO) official wearing a radioactive protective gear stands in front of …

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500,000 TONS

The flow of underground water is doubling the amount of contaminated water and spreading it to vast areas of the compound.

Exposure to the radioactive fuel contaminates the water used to cool the melted fuel from inside, and much of it leaks and pours into the basements of the reactors and turbines, and into maintenance trenches that extend to the Pacific Ocean. Plans to freeze some of the most toxic water inside the trench near the reactors have been delayed for at least 8 months due to technical challenges.

The plant reuses some of the contaminated water for cooling after partially treating it, but the additional groundwater creates a huge excess that must be pumped out.

Currently, more than 500,000 tons of radioactive water is being stored in nearly 1,000 large tanks which now cover large areas of the sprawling plant. After a series of leaks last year, the tanks are being replaced with costlier welded ones.

That amount dwarfs the 9,000 tons of contaminated water produced during the 1979 partial meltdown of the Three Mile Island nuclear plant in the United States. At Three Mile Island, it took 14 years for the water to evaporate, said Lake Barrett, a retired U.S. nuclear regulatory official who was part of the early mitigation team there and has visited the Fukushima plant.

“This is a much more complex, much more difficult water management problem,” Barrett said.

An estimated 2 trillion yen ($18 billion) will be needed just for decontamination and other mitigation of the water problem. Altogether, the entire decommissioning process, including compensation for area residents, reportedly will cost about 10 trillion yen, or about $90 billion.

All this for a plant that will never produce a kilowatt of energy again.

About 500 workers are digging deep holes in preparation for a taxpayer-funded 32 billion yen ($290 million) underground “frozen wall” around four reactors and their turbine buildings to try to keep the contaminated water from seeping out.

TEPCO is developing systems to try to remove most radioactive elements from the water. One, known as ALPS, has been trouble-plagued, but utility officials hope to achieve its daily capacity of 2,000 tons when they enter full operation next month following a final inspection by regulators.

Officials hope to treat all contaminated water by the end of March, but that is far from certain.

A summit of Pacific leaders opened in Palau on Tuesday with a call for developed nations to take action on climate change and stop overfishing the world’s largest ocean.

The host of this year’s Pacific Islands Forum (PIF), Palau President Tommy Remengesau, said small island nations had effectively become “the conscience of the world” on environmental matters.

“The ocean is our way of life,” he said at an elaborate sunset opening ceremony featuring club-wielding warriors dressed in loin cloths and palm fronds.

“It sustains and nurtures us, provides us with the basics of our Pacific island cultures, out very identities.”

Remengesau said the Pacific Ocean was “under siege” from pollution and overfishing, leaving members of the 15-nation PIF vulnerable as many of them lie barely one metre (three feet) above sea level.

“We must recognise that the long-term solution to ocean warming, rising seas and ocean acidification is a big global cut in CO2 (carbon dioxide) emissions,” he said.

This week’s meeting seeks to maintain momentum from the 2013 summit in the Marshall Islands, where Forum nations signed the Majuro Declaration, committing them to ambitious targets for cutting greenhouse gas emissions and adopting renewable energy.

Marshall Islands President Christopher Loeak said it was an opportunity to drive the message home once again ahead of a special UN summit on climate change in New York on September 23.

“Climate change must be front and centre of the regional agenda,” he said.

While the small island nations that make up the majority of Forum members have no control over the industrialised world’s greenhouse gas emissions , they can influence the direction of Pacific fisheries.

Remengesau said it was time to take a stand against industrialised fishing in the Pacific, much of which is conducted by so-called “distant water” fleets from as far afield as Europe.

The Pacific tuna industry is worth about $4.0 billion a year annually but relatively little of the money trickles back to Forum countries.

Scientists say tuna stocks are dwindling quickly, with the southern bluefin variety down an estimated 96 percent after decades of overfishing.

Throughout history, maps have played a critical role in shaping decisions — helping people determine where they are going and how to get there. Now, maps are defining a way to address methane leaks, a potent contributor to climate change. Environmental Defense Fund and Google Earth Outreach have just launched a series of maps that show methane leaks from natural gas pipelines under city streets in Boston, Indianapolis and Staten Island. The new tool has the power to greatly improve how cities and utilities can minimize methane emissions.

One of natural gas’s potential benefits over other fossil fuels is that, when burned, it produces less carbon dioxide — half as much as coal — to yield the same amount of energy. If used wisely to rapidly displace dirty coal-power plants, for example, natural gas could help the country dramatically reduce overall greenhouse-gas emissions.

For our analysis of methane emissions from local distribution pipes, Google equipped three Street View cars with methane analyzers and drove through large portions of Boston, Staten Island and Indianapolis collecting methane concentration data, GPS data and wind speed and direction data every half second. Our science team, in partnership with Colorado State University (CSU) researchers, developed a first-of-its-kind algorithm to translate the patterns of concentration data collected by the Street View cars into methane-leak rates for individual leaks. These data and the accompanying maps are designed to help the public, utilities and regulators better understand the pattern and scale of urban methane leaks.

For example, we observed one leak per mile of road driven in Boston and Staten Island, a borough of New York City. Depending on the size of those leaks, the climate impact over the next 20 years — for each leak — ranged from the equivalent of driving a car 100 miles every single day up to driving more than 9,000 miles every day. These data will allow utilities to better prioritize which leaks to repair or pipes to replace, enabling them to get rid of the larger leaks much faster than was possible before.

Helping utilities help themselves

The local utilities — like National Grid, the utility in both Boston and Staten Island, and Citizens in Indianapolis — helped validate the data and provided insight into where their repair efforts should be targeted. Leaks even larger than those we saw in our surveys are of the greatest public safety concern; but those leaks are usually identified and fixed quickly. Smaller leaks are monitored by the utilities, but can go unfixed for long periods of time, spewing significant amounts of climate pollutants into the atmosphere. The new methodologies developed to produce the maps hold the potential to benefit both public health (as leaks can sometimes trigger explosions) and the climate.

In addition to providing a picture of leak rates across cities, these maps clearly show the value of investing in a modern natural-gas infrastructure. Older pipes made of cast iron and unprotected steel can corrode as they age, making them more vulnerable to leaks. Plastic pipes, which are used in newer systems, are more durable over time and leak much less. The 200-times-lower frequency of leaks in Indianapolis, versus Boston and Staten Island, clearly indicates the value of Indianapolis’s decision to upgrade to plastic pipes.

EDF has focused on “finding the ways that work” for almost 50 years, and this collaborative mapping project is indicative of our commitment to tapping the power of science in pursuit of effective solutions. This project takes a major step toward providing local gas-distribution utilities and regulators the scientific tools to better understand methane leaks and should spur meaningful local efforts to reduce emissions of climate pollutants — with more opportunities for effective action. By continuing our collaborations with Google, CSU, local utilities and the public, we can broaden the scope of what we know, map more pollutants in more cities and spark changes to slow the planet’s warming.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook, Twitter and Google +. The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on Live Science.